Multiple studies have suggested that HBOT can enhance angiogenesis but demonstrating enhanced myocardial perfusion (presumably via therapeutic angiogenesis) in humans, have never been attempted. The investigators hypothesized that chronically ischemic viable myocardial tissue is in a state of chronic oxygen demand/delivery imbalance and that physiologic ischemia-induced angiogenesis during regenerative/repair processes, aimed to restore oxygen delivery, has been "burned out". Since all the regenerative/repair processes have common denominator: they are all energy/oxygen dependent, it might be possible that HBOT can enables the metabolic changes needed to reignite those regeneration processes, simply by supplying the missing energy/oxygen.